Suggest Treatment For Depression Caused Due To Stress

I think I m stressed? I have been dating this married man who got married while we were dating now we have had s child together but he is still with his wife who says she can accept our baby but I think she just doesnt want him to leave her. What do I do? I m abgry all the time and find myself being mean to my kids. What do I do because its so hard on me?